The present invention relates generally to a surgical kit for the preparation of a surgical gas and a method of assembling and using the same. More specifically, the present invention relates to a surgical kit and the assembly and use thereof to provide a unit dose of tamponade gas to a patient during an ophthalmic surgical procedure.
Syringes filled with a gas are useful in a number of surgical procedures requiring the injection of a gas bubble into a patient""s body. One such surgical procedure requiring the injection of a gas bubble into a patient is that of repairing a retinal tear. A retinal tear can be treated using an injected gas bubble such as sulfur hexafluoride (SF6), perfluoroethane (C2F6) or perfluoropropane (C3F8) for gas tamponage. Another such surgical procedure is that of injecting carbon dioxide (CO2) gas into a blood vessel to facilitate percutaneous angioscopy. Still another such surgical procedure is that of using injections of nitric oxide (NO) gas and NO-releasing compounds to treat male impotence, inhibition of DNA synthesis and mitochondrial respiration in tumor cells, and to relax vascular smooth muscle for control of hypertension.
Gases used for such surgical procedures are often expensive and not available in ready-to-use unit dose form. Currently, surgical gases are purchased packaged in pressurized tanks. Syringes are filled directly from the tanks using a filling line. When a syringe is disconnected from the filling line, the gas remaining in the filling line is released into the atmosphere. Thus, this method of preparing syringes for surgery is not entirely desirable due to the significant amount of gas that is wasted. Additionally, due to the busy environment of a hospital, shut-off valves on surgical gas tanks are frequently left open accidentally causing an even greater amount of gas to be wasted than when syringes are being filled.
An even more serious problem than that of wasting expensive surgical gases, is that of gas dilution within the prepared syringe prior to surgery. Syringes are sometimes prepared on the morning of the day they are to be used in a surgical procedure. Once prepared, the syringes are placed in the operating room with other surgical devices until they are used, which can be several hours later. Experiments have shown that leakage of surgical gas from a syringe over a relatively short period of time can cause clinically significant dilution of the gas thereby increasing the risk of surgical complications. For instance, the concentration of sulfur hexafluoride in a plastic syringe has been observed to decrease from 97% at 30 seconds after aspiration to 76% at 60 minutes and 2% at 18 hours after aspiration.
In U.S. Pat. No. 6,073,759 a method of preparing a gas-filled syringe is disclosed which comprises filling a high gas barrier material container with a predetermined volume of a gas, puncturing the container with the syringe needle and drawing the gas into the syringe by retracting the syringe plunger. As taught, such a method is not entirely desirable due to complications associated with the need to maintain the gas-filled container at a pressure above atmospheric pressure.
In U.S. Pat. No. 5,390,792 packaging for protective sterile containment of a rigid product is disclosed. The packaging is designed to enable circulation of sterilizing fluids about the surface of the rigid product for improved and substantially unhindered circulation of sterilizing gases throughout the interior of the packaging. Such packaging is desirable for purposes of sterilization but is not suitable for packaging of surgical gases due to the characteristics of the breathable plastic cover film.
In U.S. Pat. No. 5,377,835 a reclosable film package is disclosed which is light-tight, air-tight and reclosable made from metallized polyester foil, lined with black polyethylene. A reclosable film package is not desirable in conjunction with the packaging of surgical gases due to the preference for single-use only products.
Because of the noted shortcomings of current packaging designs, there is a need for a surgical kit designed for the preparation and use of a unit dose of surgical gas.
The present invention provides a surgical kit for the preparation of a unit dose of a surgical gas, such as a tamponade gas for ophthalmic use, and a method of using the same. The product components of the subject kit are preferably provided in a sterile blister-type packaging structure formed from a rigid resiliently flexible thermoformed plastic container and a sealed cover therefor. The plastic container preferably has a plurality of indentations molded or thermoformed therein. The indentations form interior contacting surfaces shaped in correlation with the exterior surface dimensions of the product components housed in the container so as to position the product components therein in a specified orientation. The interior contacting surfaces likewise protectively maintain product components within the packaging structure in a fixed position during shipping and handling of the surgical kit so as to secure the same from potential damage due to impacts and/or shocks imparted during shipping and/or storage.
The preferred surgical kit of the present invention includes a gas pouch filled to approximately atmospheric pressure, such as within the range of approximately 0.95 to 1.05 atmospheres of pressure with a surgical gas, a syringe with plunger, a sterilizing filter, a stopcock, a suspended spike and a capped injection needle or cannula as product components. However, numerous product component variations may be included in the subject surgical kit, depending on the surgical procedure for which the kit is prepared, to provide for the preparation of a unit-dosage of gas for use in surgery.
The gas-filled syringe is prepared just before surgery by connecting the sterilizing filter, the stopcock and the suspended spike respectively to the syringe. The suspended spike is then used to perforate a plug positioned within a filling nozzle of the gas pouch. The desired volume of surgical gas is drawn into the syringe by withdrawing the plunger a specific distance from within the syringe interior as dictated by the volume desired. The stopcock is then closed to seal the gas pouch prior to removal of the syringe. A capped injection needle or cannula is then connected to the syringe for use in a surgical procedure. Alternatively, a syringe with a capped injection needle or cannula can be directly used to perforate the plug positioned within the filling nozzle of the gas pouch depending on the requirements of the specific surgical procedure.
If a gas/air mixture is desired for the surgical procedure, the syringe and the sterilizing filter are removed from the stopcock. To prepare a gas/air mixture, if desired, the desired volume of air is drawn into the syringe through the sterilizing filter by withdrawing the plunger a specific distance from within the syringe interior as dictated by the volume desired. The sterilizing filter is then removed from the syringe and the capped injection needle or cannula connected to the syringe for use in a surgical procedure.
Accordingly, it is an object of the present invention to provide a surgical kit for the preparation of a surgical gas.
Another object of the present invention is to provide a surgical kit for the preparation of a unit-dose of tamponade gas.
Another object of the present invention is to provide a surgical kit for the preparation of a unit-dose gas/air mixture.
Another object of the present invention is to provide a method of using product components of a surgical kit for the preparation of a tamponade gas.
Still another object of the present invention is to provide a method of using product components of a surgical kit for the preparation of a unit-dose gas/air mixture.
These and other objectives and advantages of the present invention, some of which are specifically described and others that are not, will bercome apparent from the drawings, detailed description and claims that follow.